Prospective Study of Diet, Physical Activity, BMI and Risk of Pulmonary Embolism Venous thromboembolism (VTE) represents a spectrum of disease that includes deep venous thrombosis (DVT) and pulmonary embolism (PE). Given the high incidence and sudden mortality associated with PE in the elderly, primary prevention is of vital importance. Unfortunately, our understanding of modifiable risk factors -- that could be used to guide the development of primary prevention strategies -- is very limited. The proposed study will address this information gap and bring together a multidisciplinary group of VTE clinical researchers and cardiovascular/nutrition epidemiologists at the Channing Laboratory, Brigham and Women's Hospital and Massachusetts General Hospital. We will use 2 large prospective observational cohort studies to examine the relationship between dietary factors, physical activity, body mass index (BMI) and risk of PE among elderly participants in the Nurses' Health Study (NHS) and the Health Professionals' Follow-Up Study (HPFS), using data from 1985 to 2002. NHS is an ongoing prospective cohort study of 121,700 female nurses, age 50-55 in 1986 (approx. 650 PE cases). HPFS is an ongoing prospective cohort study of 51,529 men in health professions age 40-75 in 1986 (approx. 350 PE cases). We will address the following questions: [unreadable] [unreadable] Are major dietary patterns (Prudent vs. Western), and specific dietary factors (i.e., omega-3 fatty acids, trans fats, dietary fiber, antioxidants, Vitamin K-containing foods) associated with different risks of PE? Is the risk of PE modified by increasing levels of physical activity? Within the normal range, is BMI positively associated with PE? Exposure information was gathered by validated measures, including the Semiquantitative Food Frequency Questionnaire, the Physical Activity Questionnaire, and an extensive list of covariates collected biannually in NHS and HPFS. We will validate reported cases of PE using supplementary questionnaires and medical records; such data collection was initiated two decades ago and the current grant would fund the completion of outcome validation, data management, and testing of the hypotheses listed above. Statistical power is >80% for all of proposed aims. The project would lay the foundation for future work on genetic markers of PE risk in these large cohort studies. We hope to identify and quantify risk factors for PE that lead to public health interventions that effectively decrease the incidence of VTE in the elderly population. Project Narrative: Venous thromboembolism is a common and deadly disease, especially among the elderly. We propose to study >150,000 adults in two large prospective cohort studies (the Nurses' Health Study and Health Professionals' Follow-up Study) to learn how modifiable risk factors related to diet, physical activity, and body mass index affect the risk of pulmonary embolism. We believe that quantifying these modifiable risk factors will lead to public health interventions that decrease the incidence of pulmonary embolism in the elderly population. [unreadable] [unreadable] [unreadable]